Brake-cylinder piston-packing.



H. C. LOUDENBECK.

BRAKE CYLINDER PISTON PACKING.

APPLICATION FILED SEPT. 2|. I917- l1 ,3 1 4, 143 Patented Aug. '26,1919.

INVENTOH Harry Loudenbeck UNITED STATES PATENT OFFICE.

PENNSYLVANIA, ASSIGNOR TO THE OF WILMERDING, PENNSYLVANIA,

A CORPORATION OF PENNSYLVANIA.

BRAKE-CYLINDER PISTON-PACKING.

Specification of Letters Patent.

Patented Aug. 26, 1919.

Application filed September 21, 1917. Serial No. 192,510.

To all whom it may concern:

Be it known that I, HARRY C. LOUDEN- BECK, a citizen of the UnitedStates, residing at Pittsburgh, in the county of Allegheny and State ofPennsylvania, have invented new and useful Improvements inBrake-Cylinder Piston-Packing, of which the following is aspecification.

This invention relates to packing, and more particularly to cuppedpacking as employed in pistons adapted to work in cyliners.

Piston packing of the above character is ordinarily made of leather andin order to hold the acking tightly against the walls of the cy inder,it is usual to employ a resilient expander ring which of the packing andacts against the packing.

By reason of the increasing scarcity and high price of leather, oneob]ect of my in vention is to provide a piston packing formed of othermaterial.

Another object of my invention is to provide a piston packing which willhave inherent resiliency to press firmly against the cylinder wall andthus dispense with the use of expander rings.

Another disadvantage in the use of leather for piston packing is that itbecomes more or less porous to fluids and liquids in service, so thatleakage occurs through the packing, and a further object of my inventionis'to provide a leak proof packing.

In the accompanying drawing; F1gure 1 is a section on line'1-1 of Fig. 2of a pmton packing constructed in accordance with my invention; Fig. 2 aplan now thereof; and Fig. 3 an enlarged transverse section of a portionof the packing According to my inventlon, is formed of layers of groundcork w1th an intermediate layer of fabric, the resulting pile beingpressed into the desired cup shape by means of a die mold and press.

The preferred process of making the the packing is fitted inside packingis covered by my co-pending application Serial No. 192,485, filedSeptember 21, 1917, and consists briefly in providing disks cut fromsheets of pressed ground corkmixed with a suitable binder and disks offabric such as duck or canvas.

The round cork disks are coated on one side with glue and referably thefabric disk is also coated wit 1 glue. A pile is then made of two groundcork disks with an intermediate disk of fabric and the pile is placed ina die mold where it is formed into the cup shape while the glue remainsunset.

The pile is retained in the die mold and is heat treated to set the glueand is then ready for service.

As shown in Fig. 1 of the drawing, the packing comprises a flange 1which is secured to the piston and a flange 2 which bears againstthewalls of the cylinder.

The flange 2 is flared outwardly and it has been found that theresiliency given to p i the packing by the reinforcing fabric layer isample to maintain the packing tightly against the walls of the pistoncylinder, so that it is not necessary to employ an expander ring forthat urpose. Furthermore, the packing retains t 115 resiliencythroughout the life of the packing.

- Thefabric of the intermediate layer 3 of the acking is preferably duckor canvas.

T e interposition of the fabric layer while reinforcing the cork layers,also prevents breaking of the packingat the bend while being formed aswell as in service.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is

A cup shaped piston packing formed from pressed disks composed of groundcork with an intermediate layer .of duck fabric.

In testimony whereof I have hereunto set my hand.

HARRY G. LOUDENBEOK.

